Effect of wet antenna attenuation on propagation data statistics

Wet antenna attenuation during rain events is examined through carrying out simulated rain experiments. These were conducted on the receiving antenna of the Vancouver ACTS terminal under conditions similar to those prevalent when the propagation data on the Vancouver ACTS path were collected. The findings from these experiments are used to estimate path attenuation data for that path by adjusting the collected data for wet antenna attenuation via two different models. Primary and secondary statistics of the path attenuation data derived from the models at the two ACTS frequencies, nominally 20 and 27 GHz, are computed and compared with those for the unadjusted, measured data. This was done for the four-year period of December 1993 to November 1997 and includes average and worst month cumulative distribution functions and fade-duration and fade-slope statistics. While the two models yield similar statistics, these differ significantly from those derived from the unadjusted data. The comparison of the two sets of statistics suggests that the use of those of the unadjusted data to represent path attenuation would grossly exaggerate the requirements for system design